Gear cutter

A method of cutting gears and prolonging cutter life comprising:

• (a) electrically controlling a variable speed cutter having a first electrically activated variable speed means for controlling cutting speed and a second variable speed means for providing variable speed cutter shift;
• (b) electrically measuring and calculating the units of power expended in relation to a predetermined amount of cutter shift of an electrically activated variable speed cutter for generating a desired gear profile in relation to the size and material of the gear blank, feed rate and the new or resharpened condition of the cutter to provide a predetermined value of power ideally expended in cutting a gear;
• (c) electrically controlling an electrically activated variable speed means for providing a variable workpiece feed for a gear blank;
• (d) measuring the amount of variable power actually expended during the operation of said variable speed cutter;
• (e) electrically comparing said variable power actually expended during the operation of said variable speed cutter with said predetermined value;
• and
• (f) varying said variable workpiece feed, said variable power during the operation of said cutter and said cutter shift to vary said variable power actually expended in correlation with said predetermined value of the units of power ideally expended in relation to the amount of said cutter shift to provide a predetermined gear profile for the gear blank workpiece.

A method of hobbing which provides gears of increased accuracy while improving hob cutter life comprising:

• (a) electrically measuring and calculating the units of power expended in relation to a predetermined amount of hob shift necessary to generate an optimal gear tooth profile in relation to the size and material of a gear blank, feed rate and the new or resharpened condition of said hob to provide a predetermined value of power ideally expended in cutting a desired gear;
• (b) electrically controlling the variable power to rotate an electrically activated variable speed hob cutter and electrically controlling an electrically activated variable speed hob shift;
• (c) electrically controlling an electrically activated variable feed rate of a workpiece to said hob cutter;
• (d) measuring the units of power actually expended to rotate said variable speed hob cutter;
• (e) electrically comparing said variable power actually expended with said predetermined value;
• and
• (f) electronically increasing or decreasing said variable feed rate and said variable power for the rotation of said hob cutter and said hob shift in correlation with said predetermined value to duplicate the cutting conditions and said power expended in cutting said desired gear in generating an optimal tooth profile.

A gear cutting machine comprising:

• (a) a workpiece support, said workpiece support including a first electrically controlled variable speed electric motor for providing variable workpiece feed and impulses corresponding to workpiece feed;
• (b) driving means wherein said driving means comprises a second variable speed electric motor for driving an electrically activated variable speed cutter said driving means further including a third electrically activated variable speed motor for varying the shift of said variable speed cutter including a cutter support providing separate cutter rotation drive and cutter shift displacement drive and wherein said second variable speed electric motor is operatively connected to said cutter rotation drive and said third electrically activated variable speed motor is operatively connected to said cutter shift displacement drive;
• (c) an electrical controller for measuring and providing impluses of increases and decreases in drive power utilized in operating said second variable speed electric motor and for increasing or decreasing the speed of said first and said third variable speed electric motors;
• (d) an electrical central processing unit for receiving and comparing said impluses received from said controller with predetermined values from a main memory unit of the computer and generating corrective power impulses for said second variable speed electric motor or for increasing the speed of said third variable speed electric motor;
• and
• (e) a computer having a main memory unit with predetermined value of units of power ideally required for the material and size of the gear blank, workpiece feed and said shift of said variable speed shift to provide signals to said electrical central processing unit for computing the necessary change or changes in power for driving said electrically activated cutting element and for increasing or decreasing the speed of said third variable speed electric motor and providing corrective impulses to said electrical controller wherein said computer main memory unit in combination with said central processing unit varies said power for said first variable speed motor and varies the speed of said third variable speed motor in response to a detected change in the power utilized for driving said second motor within the response time of the computer and the electrical circuits that is accomplished within millionths of a second to provide the necessary changes in drive power and cutter shift during the cutting of the gear blank to duplicate a previous gear cutting operation.

A gear cutting machine for cutting gears of increased accuracy comprising:

• (a) a variable speed cutter including a cutter support providing separate cutter rotation drive and cutter shift displacement drive wherein said cutter rotation drive is driven by a first variable speed electric motor providing rotational drive and wherein said cutter shift displacement drive is driven by a second variable speed electric motor for providing shift for said variable speed cutter;
• (b) a controller for measuring and varying the power for driving said first variable speed electric motor and the speed of said second variable speed electric motor of said variable speed cutter;
• (c) a workpiece support wherein said workpiece support is driven by a third variable speed electric motor to provide workpiece feed;
• and
• (d) a central processing unit for providing instructions to said controller and controlling said variable speed cutter by comparing the power actually required to drive said cutter with a predetermined ideal power value and varying said power for driving said first variable speed electric motor and varying the speed of said second variable speed electric motor in response to a detected change in the power utilized for driving said first motor to provide the necessary changes in drive power and cutter shift to duplicate a priviously cut gear in accordance with a predetermined cutting program.